Dual function air diverter and variable area fan nozzle

ABSTRACT

A modulating fan air diverter and annular air-oil cooler for a gas turbine engine located in the inner fixed structure adjacent to the core cowl is provided. The fan air diverter modulates between an open position, corresponding to maximum fan nozzle area and airflow through the air-oil cooler, and a closed position, corresponding to minimum fan nozzle area and airflow through the air-oil cooler. As such, the device is capable of supporting dual functions of engine heat management as well as engine performance and fan stability.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.14/513,409 filed on Oct. 14, 2014, which claims priority to U.S.Provisional Application Ser. No. 61/926,661 filed on Jan. 13, 2014, thecontents each of which are incorporated herein by reference thereto.

FIELD OF THE DISCLOSURE

The present disclosure generally relates to gas turbine engines, andmore particularly, to a dual function fan air diverter and variable areafan nozzle for use with gas turbine engines.

BACKGROUND OF THE DISCLOSURE

A gas turbine engine is typically provided with an oil tank as well asmeans for cooling the oil circulated therethrough. In someconfigurations, a gas turbine engine may employ an annular-type air-oilcooler that is circumferentially positioned about the low pressurecompressor in the inner fixed structure section of the inner cowl andprovided with cooling fins disposed in general fluid communication witha fan duct and nozzle of the gas turbine engine. More specifically, theinner surface of the outer nacelle and the outer surface of the innercowl at the low pressure compressor section define a fan duct and nozzlethrough which fan airflow is received. The air-oil cooler cooling finsextend into the fan duct so as to dissipate excess heat from the oilbeing circulated through the annular air-oil cooler into the fan airflowpassing thereby.

In some gas turbine engine configurations, an annular fan air diverterassembly is provided to modulate the amount of fan airflow which passesthrough a plurality of cooling fins of the annular air-oil cooler, andthereby modulate the oil temperature. The annular air-oil cooler inconjunction with the modulating fan air diverter is part of the engineheat management system. These configurations may also employ separateassemblies for modulating the fan nozzle area to improve performance andfan stability during operation of the gas turbine engine. Havingassemblies that are separately installed and individually controlledcome with increased costs, added complexity and other drawbacks. Thepresent disclosure is directed at addressing one or more of thesedeficiencies.

SUMMARY OF THE DISCLOSURE

In accordance with one aspect of the disclosure, a fan air diverter fora gas turbine engine having at least an inner cowl and an annularair-oil cooler is provided. The fan air diverter may include a nozzleflap disposed circumferentially about the inner cowl and coaxiallyadjacent to the annular air-oil cooler, and an actuator assemblyoperatively coupling the nozzle flap to the inner cowl. The nozzle flapmay be pivotally coupled to the inner cowl and selectively movablerelative to the annular air-oil cooler between an open position and aclosed position. The actuator assembly may be configured to actuate thenozzle flap between the open position and the closed position.

In accordance with another aspect of the disclosure, an oil coolingassembly for a gas turbine engine having at least an inner cowl isprovided. The oil cooling assembly may include an annular air-oil coolercircumferentially disposed about the inner cowl, and a fan air divertercircumferentially disposed about the inner cowl and coaxially adjacentto the cooling fins. The annular air-oil cooler may include an integralannular oil tank and a plurality of cooling fins radially extendingtherefrom. The cooling fins may be disposed in at least partialcommunication with a fan duct and nozzle of the gas turbine engine forreceiving fan airflow. The fan air diverter may be selectively movablerelative to the cooling fins so as to modulate fan airflow.

In accordance with yet another aspect of the disclosure, a gas turbineengine is provided. The gas turbine engine may include an outer nacelleand an inner cowl defining a fan duct and nozzle for receiving fanairflow, an annular air-oil cooler disposed circumferentially about theinner cowl and in communication with the fan duct and nozzle, at leastone nozzle flap disposed circumferentially about the inner cowl andcoaxially adjacent to the annular air-oil cooler, and an actuatorassembly operatively coupling the nozzle flap to the inner cowl. Thenozzle flap may be pivotally coupled to the inner cowl and selectivelymovable relative to the annular air-oil cooler between an open positionand a closed position. The actuator assembly may be configured toactuate the nozzle flap between the open position and the closedposition so as to modulate fan airflow through the air-oil cooler forheat management and to vary either the fan nozzle throat or exit areafor engine performance and fan stability purposes.

These and other aspects of this disclosure will become more readilyapparent upon reading the following detailed description when taken inconjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partial, cross-sectional view of the front section of a gasturbine engine having a fan air diverter in the closed position;

FIG. 2A is an axial, cross-sectional view of a section of an annularair-oil cooler;

FIG. 2B is an axial, cross-sectional view of a section of a dualfunction air-oil cooler with integral oil tank;

FIG. 3 is a partial, cross-sectional view of a low pressure compressorsection of a gas turbine engine having a fan air diverter in the openedposition;

FIG. 4 is a partial, cross-sectional view of a low pressure compressorsection of a gas turbine engine having a fan air diverter with fore andaft nozzle flaps;

FIGS. 5A-5C are cross-sectional views of a fan air diverter with foreand aft nozzle flaps in fully open, intermediate and fully closedpositions;

FIGS. 6A-6C are cross-sectional views of another fan air diverter withfore and aft nozzle flaps in fully open, intermediate and fully closedpositions;

FIGS. 7A-7C are cross-sectional views of yet another fan air diverterwith fore and aft nozzle flaps in fully open, intermediate and fullyclosed positions;

FIG. 8 is an axial, cross-sectional view of one actuator assembly of afan air diverter;

FIG. 9 is a partial, cross-sectional view of the actuator assembly ofFIG. 8;

FIG. 10 is an axial, cross-sectional view of another actuator assemblyof a fan air diverter; and

FIG. 11 is a partial, cross-sectional view of the actuator assembly ofFIG. 10.

While the present disclosure is susceptible to various modifications andalternative constructions, certain illustrative embodiments thereof havebeen shown in the drawings and will be described below in detail. Itshould be understood, however, that there is no intention to be limitedto the specific forms disclosed, but on the contrary, the intention isto cover all modifications, alternative constructions, and equivalentsfalling with the spirit and scope of the present disclosure.

DETAILED DESCRIPTION

Referring to FIG. 1, the front section of a gas turbine engine 100having an exemplary oil cooling assembly 102 constructed in accordancewith the present disclosure is provided. Among other things, the frontsection of the gas turbine engine 100 may generally include an outernacelle 104, an inner cowl 106, a splitter 108, fan blades 112, exitguide vanes 114 and a fan duct and nozzle 110 associated therewith.Moreover, as indicated by the arrows shown, airflow 116 entering intothe gas turbine engine 100 may be split by the splitter 108 into bypassor fan airflow 118 flowing through the fan duct and nozzle 110 andprimary or core airflow 120 flowing into the low pressure compressor.

The oil cooling assembly 102 of the gas turbine engine 100 of FIG. 1 maybe circumferentially disposed about an outer surface of the inner fixedstructure in front of the inner cowl 106, and generally composed of atleast one annular air-oil cooler 122 and an annular fan air diverter 124coaxially adjacent thereto. With further reference to the partial, axialcross-section provided in FIG. 2A, the annular air-oil cooler 122 mayinclude an arcuate finned oil channel 126 through which oil iscirculated for cooling. The annular air-oil cooler 122 may furtherinclude a plurality of cooling fins 128 radially extending thereaboutwhich conduct heat from the oil within the finned oil channel 126 anddissipate the heat into the bypass or fan airflow 118 passing thereby.In other embodiments, such as shown in the partial, axial cross-sectionprovided in FIG. 2B, an integral oil tank may be provided along theinner surface of the annular air-oil cooler 122.

As further shown in FIG. 1, the cooling fins 128 of the annular air-oilcooler 122 may extend into the fan duct and nozzle 110 and into the pathof the fan airflow 118. Correspondingly, the fan air diverter 124 mayprovide at least one nozzle flap 132 adjacent to the inlet-side of thecooling fins 128 of the annular air-oil cooler 122 in a manner whichenables not only modulation of oil cooling, but also variability of thefan nozzle exit or throat area. Specifically, the nozzle flap 132 may bepivotally or otherwise movably disposed relative to the cooling fins128, and configured to selectively direct fan airflow 118 toward or awayfrom the cooling fins 128. Moreover, the nozzle flap 132 may be actuatedinto a fully closed position, as shown in FIG. 1 for example, to divertfan airflow 118 away from the cooling fins 128, minimize cooling andreduce the fan nozzle area. The nozzle flap 132 may also be actuatedinto a fully open position, as shown in FIG. 3 for example, tocompletely expose the cooling fins 128 to the fan airflow 118, maximizecooling and increase the fan nozzle area. The nozzle flap 132 may alsobe actuated into any intermediate position between the fully closed andfully open positions.

In other embodiments, the fan air diverter 124 may optionally provide anozzle flap 134 at the aft or outlet-side of the annular air-oil cooler122 in addition to the nozzle flap 132 at the fore or inlet-side of theannular air-oil cooler 122 to provide further variability of the fannozzle area, as shown for example in FIG. 4. In still furtherembodiments, the configuration of the fan air diverter 124 and eachnozzle flap 132, 134 thereof may be varied as illustrated in FIGS. 5-7.In particular, each nozzle flap 132, 134 may be configured such thateither the leading edge or trailing edge thereof is hinged relative tothe inner cowl 106 or the cooling fins 128.

As shown in FIGS. 5A-5C for example, the trailing edge of the forenozzle flap 132 is hinged or otherwise coupled to the inlet-side of thecooling fins 128 so as to open or close relative to the outer surface ofthe inner cowl 106, while the leading edge of the aft nozzle flap 134 ishinged to the outlet-side of the cooling fins 128. In the fully openpositions of FIG. 5A, the fan air diverter 124 may provide a generallyconverging fan airflow 118 through the fan nozzle 110 and the coolingfins 128. In the intermediate positions of FIG. 5B, the fan air diverter124 may provide a moderately converging-diverging fan airflow 118, or afan airflow 118 which converges toward the outlet-side of the coolingfins 128, and then diverges at least temporarily thereafter. The fullyclosed positions of FIG. 5C provide similar effects to the positions ofFIG. 5B but to a greater degree, and thereby provides an increasedconverging-diverging fan airflow 118.

In FIGS. 6A-6C, the leading edge of the fore nozzle flap 132 is hingedto the inner cowl 106, while the leading edge of the aft nozzle flap 134is hinged to the outlet-side of the cooling fins 128. As in FIGS. 5A-5C,the fully open, intermediate and fully closed positions of FIGS. 6A-6Cmay similarly provide generally converging, moderatelyconverging-diverging and increased converging-diverging fan airflows118, respectively. Furthermore, in FIGS. 7A-7C, the leading edge of thefore nozzle flap 132 is hinged to the inner cowl 106 as in FIGS. 6A-6C,while the trailing edge of the aft nozzle flap 134 is hinged to theinner cowl 106. Similar to previous embodiments, the fully open,intermediate and fully closed positions of FIGS. 7A-7C may providegenerally converging, moderately converging-diverging and increasedconverging-diverging fan airflows 118, respectively. By adjusting thecontour of the inner cowl 106 and/or outer nacelle 104 in the vicinityof the annular air-oil cooler 122 and fan air diverter 124, other nozzleconfigurations can also be realized. Other alternate combinations ofpositions or other intermediate positions not shown will be apparent tothose of skill in the art.

Turning now to FIGS. 8 and 9, cross-sectional views of one exemplaryembodiment of an actuation system assembly 136 for the fan air diverter124 are provided. As shown, the actuation system assembly 136 mayinclude a sync ring 138 that is circumferentially and coaxially disposedbetween the low pressure compressor and the nozzle flap 132, andconfigured to be rotatable between a first angular position and a secondangular position about the engine axis. The actuation system assembly136 may further include a plurality of idler links 140 radially couplingthe sync ring 138 to the nozzle flaps 132 as shown. Moreover, each idlerlink 140 may be pivotally configured such that rotating the sync ring138 in the first direction or toward the first angular position movesthe nozzle flap 132 into the open position, and rotating the sync ring138 in the opposing, second direction or toward the second angularposition moves the nozzle flap 132 into the closed position. Theactuation system assembly 136 may further include a plurality of rollerguides 142 rotatably disposed relative to the sync ring 138 to enablerotation of the sync ring 138 with reduced friction. The roller guides142 may be radially provided along the inner edge of the sync ring 138as shown and/or along the outer edge thereof.

Referring to FIGS. 10 and 11, axial and side cross-sections of anotherexemplary embodiment of an actuation system assembly 136 are provided.As in the embodiment of FIGS. 8 and 9, the actuation system assembly 136of FIGS. 10 and 11 may employ a sync ring 138 and a plurality of idlerlinks 140 radially disposed between the sync ring 138 and the nozzleflaps 132. Rather than roller guides 142, however, the actuation systemassembly 136 may employ a plurality of bumpers 144 radially distributedbetween the sync ring 138 and a guide ring 146. In one possibleimplementation, each idler link 140 may include ball ends 148 whichpivotally couple to each of the nozzle flap 132 and the sync ring 138 asshown in FIG. 11 to form ball joints 150. Furthermore, the bumpers 144may be formed of a low-friction material with shock absorbentproperties. The bumpers 144 may also be shimmed to allow clearanceadjustments between the sync ring 138 and the guide ring 146.

As in previous embodiments, the actuation system assembly 136 of FIGS.10 and 11 may be similarly configured such that rotating the sync ring138 in the first direction or toward the first angular position pivotsthe idler links 140 in a manner which moves the nozzle flap 132 into theopen position, and rotating the sync ring 138 in the opposing, seconddirection or toward the second angular position pivots the idler links140 in a manner which moves the nozzle flap 132 into the closedposition. The actuation system assemblies 136 of FIGS. 8-11 may also beimplemented using any other kinematic mechanism for converting linear orrotary motion of an actuator into a rotation of the sync ring 138, orany other suitable means for modulating the nozzle flaps 132, 134 ondemand. Furthermore, the modulating fan air diverter 124 and theassociated actuation system assembly 136 may be installed in thestationary portion of the inner cowl 106, or the inner fixed structure,so as not to be impacted by or in otherwise interference with theopening of associated engine core cowl doors. Still further, while theforegoing actuation system assemblies 136 were disclosed in relation tofore or inlet-side nozzle flaps 132, similar actuator assemblies may beseparately provided and appropriately configured for any aft oroutlet-side nozzle flaps 134.

The foregoing disclosure is exemplary rather than defined by thelimitations within. Various non-limiting embodiments are disclosedherein, however, one of ordinary skill in the art would recognize thatvarious modifications and variations in light of the above teachingswill fall within the scope of the appended claims. It is therefore to beunderstood that within the scope of the appended claims, the presentdisclosure may be practiced other than as specifically described. Forthat reason, the appended claims should be studied to determine truescope and content.

What is claimed is:
 1. A fan air diverter for a gas turbine enginehaving at least an inner cowl radially inward from an outer nacelle andan annular air-oil cooler, the fan air diverter comprising: a nozzleflap disposed about the inner cowl and coaxially adjacent to the annularair-oil cooler, the nozzle flap being pivotally coupled to the innercowl at a point of securement that is axially spaced from the annularair-oil cooler, the nozzle flap being selectively movable relative tothe annular air-oil cooler between an open position and a closedposition, wherein the annular air-oil cooler includes a plurality ofcooling fins that extend radially outward past the point of securement;and an actuation system assembly operatively coupled to the nozzle flap,the actuation system assembly being configured to actuate the nozzleflap between the open position and the closed position, wherein theactuation system assembly comprises: at least one sync ring operativelycoupled to the nozzle flap, the at least one sync ring being rotatablebetween a first angular position and a second angular position about anaxis of the gas turbine engine, wherein rotation of the at least onesync ring to the first angular position moves the nozzle flap to theopen position, and rotation of the at least one sync ring to the secondangular position moves the nozzle flap to the closed position, whereinthe nozzle flap provides at least one of a converging fan airflowthrough a fan nozzle and the cooling fins, a converging-diverging fanairflow through the fan nozzle and the cooling fins, and a fan airflowthat converges toward an outlet-side of the cooling fins.
 2. The fan airdiverter of claim 1, wherein the nozzle flap includes two or morearcuate segments circumferentially disposed about a surface of the innercowl, and about an inner fixed structure at a fore of a core cowl. 3.The fan air diverter of claim 1, wherein the nozzle flap is axiallypositioned forward of the annular air-oil cooler, the nozzle flap havinga leading edge that is pivotally hinged to a surface the inner cowl anda trailing edge that is movable between the open position and the closedposition relative to an inlet of the annular air-oil cooler.
 4. The fanair diverter of claim 1, wherein the nozzle flap, in the open position,enables fan airflow toward a corresponding portion of the annularair-oil cooler and provides an increased fan nozzle area, and in theclosed position, diverts fan airflow away from a corresponding portionof the annular air-oil cooler and provides a decreased fan nozzle area.5. The fan air diverter of claim 1, wherein the nozzle flap is axiallypositioned aft of the annular air-oil cooler, the nozzle flap having aleading edge that is movable between the open position and the closedposition relative to an outlet of the annular air-oil cooler and atrailing edge that is pivotally hinged to a surface of the inner cowl.6. The fan air diverter of claim 1, wherein the actuation systemassembly further comprises: a plurality of idler links radially couplingthe at least one sync ring to the nozzle flap, and wherein the at leastone sync ring is circumferentially disposed between a low pressurecompressor case and the nozzle flap.
 7. The fan air diverter of claim 6,wherein the actuation system assembly further comprises a plurality ofroller guides disposed between the at least one sync ring and an outersurface of the low pressure compressor case so as to enable rotation ofthe at least one sync ring about a central axis of the gas turbineengine.
 8. The fan air diverter of claim 6, wherein the actuation systemassembly further comprises a guide ring circumferentially disposedbetween the at least one sync ring and an outer surface of the lowpressure compressor case, the guide ring being rigidly coupled to anassembly mounted to the gas turbine engine, the at least one sync ringbeing slidably rotatable about the guide ring via a plurality of bumpersdisposed therebetween.
 9. An oil cooling assembly for a gas turbineengine having at least an inner cowl, comprising: an annular air-oilcooler disposed about the inner cowl, the annular air-oil coolerincluding an integral annular oil tank and a plurality of cooling finsradially extending therefrom, the cooling fins being disposed in atleast partial communication with a fan duct and a fan nozzle; and a fanair diverter disposed about the inner cowl and coaxially adjacent to thecooling fins, the fan air diverter being selectively movable relative tothe cooling fins to provide at least one of a converging fan airflowthrough the fan nozzle and the cooling fins, a converging-diverging fanairflow through the fan nozzle and the cooling fins, and a fan airflowthat converges toward an outlet-side of the cooling fins, wherein theplurality of cooling fins extend radially outward past a point ofpivotal securement of the fan air diverter to the inner cowl, whereinthe point of pivotal securement of the fan air diverter to the innercowl is axially spaced from the annular air-oil cooler.
 10. The oilcooling assembly of claim 9, wherein the fan air diverter is selectivelymovable between an open position and a closed position, the fan airdiverter in the open position enabling fan airflow toward acorresponding portion of the annular air-oil cooler and providing anincreased fan nozzle area, the fan air diverter in the closed positiondiverting fan airflow away from a corresponding portion of the annularair-oil cooler and providing a decreased fan nozzle area.
 11. The oilcooling assembly of claim 9, wherein the fan air diverter comprises anozzle flap pivotally coupled to the inner cowl at the point of pivotalsecurement, the nozzle flap being selectively movable relative to thecooling fins between an open position and a closed position.
 12. The oilcooling assembly of claim 11, wherein the nozzle flap is axiallypositioned forward of the cooling fins, the nozzle flap having a leadingedge that is pivotally hinged to a surface the inner cowl at the pointof pivotal securement and a trailing edge that is movable between theopen position and the closed position relative to an inlet of theannular air-oil cooler.
 13. The oil cooling assembly of claim 11,wherein the nozzle flap is axially positioned aft of the cooling fins,the nozzle flap having a leading edge that is movable between the openposition and the closed position relative to an outlet of the annularair-oil cooler and a trailing edge that is pivotally hinged to astationary surface of the inner cowl at the point of pivotal securement.14. The oil cooling assembly of claim 9, wherein the fan air divertercomprises a fore nozzle flap pivotally disposed adjacent to theplurality of cooling fins at an inlet of the annular air-oil cooler andan aft nozzle flap pivotally disposed adjacent to the plurality ofcooling fins at an outlet of the annular oil cooler, each of the forenozzle flap and the aft nozzle flap being independently actuatable so asto modulate fan airflow and fan nozzle area.
 15. The oil coolingassembly of claim 9, wherein the fan air diverter comprises a nozzleflap and an actuation system assembly operatively coupled to the nozzleflap, the actuation system assembly being configured to selectively movethe nozzle flap between an open position and a closed position relativeto the plurality of cooling fins.
 16. The oil cooling assembly of claim15, wherein the actuation system assembly comprises: at least one syncring circumferentially disposed between an outer surface of anassociated low pressure compressor case and the nozzle flap, the atleast one sync ring being rotatable between a first angular position anda second angular position about a central axis of the gas turbineengine; and a plurality of idler links radially coupling the at leastone sync ring to the nozzle flap, the idler links being pivotallyconfigured such that rotation of the at least one sync ring to the firstangular position moves the nozzle flap to the open position, androtation of the at least one sync ring to the second angular positionmoves the nozzle flap to the closed position.
 17. A gas turbine engine,comprising: an outer nacelle; an inner cowl defining a fan duct andnozzle along with the outer nacelle for receiving fan airflow; anannular air-oil cooler disposed circumferentially about the inner cowland in communication with a fan nozzle; at least one nozzle flapdisposed about the inner cowl and coaxially adjacent to the annularair-oil cooler, the at least one nozzle flap being pivotally coupled tothe inner cowl at a point of securement that is axially spaced from theannular air-oil cooler and selectively movable relative to the annularair-oil cooler between an open position and a closed position, whereinthe annular air-oil cooler includes a plurality of cooling fins thatextend radially outward past the point of securement; and an actuationsystem assembly operatively coupled to the at least one nozzle flap, theactuation system assembly being configured to actuate the at least onenozzle flap between the open position and the closed position so as tomodulate fan airflow and to provide at least one of a converging fanairflow through the fan nozzle and the plurality of cooling fins, aconverging-diverging fan airflow through the fan nozzle and theplurality of cooling fins, and a fan airflow that converges toward anoutlet-side of the plurality of cooling fins.
 18. The gas turbine engineof claim 17, wherein the at least one nozzle flap includes a fore nozzleflap pivotally disposed adjacent to an inlet of the annular air-oilcooler and an aft nozzle flap pivotally disposed adjacent to an outletof the annular air-oil cooler, the fore nozzle flap having a leadingedge that is pivotally hinged to a surface of the inner cowl and atrailing edge that is movable between the open position and the closedposition relative to the inlet of the annular air-oil cooler, the aftnozzle flap having a leading edge that is movable between the openposition and the closed position relative to the outlet of the annularair-oil cooler and a trailing edge that is pivotally hinged to astationary surface of the inner cowl.
 19. The gas turbine engine ofclaim 17, wherein the actuation system assembly comprises: at least onesync ring circumferentially disposed between an outer surface of a lowpressure compressor case and the at least one nozzle flap, the at leastone sync ring being rotatable between a first angular position and asecond angular position about a central axis of the gas turbine engine;and a plurality of idler links radially coupling the at least one syncring to the at least one nozzle flap, the idler links being pivotallyconfigured such that rotation of the at least one sync ring to the firstangular position moves the at least one nozzle flap to the openposition, and rotation of the at least one sync ring to the secondangular position moves the at least one nozzle flap to the closedposition and wherein the actuation system assembly is installed in aninner fixed structure of the inner cowl in a manner configured tominimize any interference with one or more core cowl doors of the gasturbine engine.
 20. The gas turbine engine of claim 19, wherein theactuation system assembly comprises a guide ring circumferentiallydisposed between the at least one sync ring and the outer surface of thelow pressure compressor case, the guide ring being rigidly coupled to anassembly mounted to the gas turbine engine, the at least one sync ringbeing rotatable about the guide ring sliding on one or more bumpers.